1. Field of the Invention
The present invention relates to an apparatus for recognizing a working height of a carrier in a semiconductor device test handler, and more particularly, to an apparatus and method for recognizing a working height of a carrier in a semiconductor device test handler enabling to measure to reset the working height of the carrier in accordance with a species of the semiconductor devices and replacing components such as a tray and a change kit fast and precisely when various kinds of semiconductor devices are tested in the handler.
2. Discussion of the Related Art
Generally, semiconductor devices produced in a production line undergo tests for checking whether to be good or fail before shipment.
A handler is a device for testing such semiconductor devices. The handler uses a semiconductor device carrier to transfer semiconductor devices received on a tray to another process line automatically, loads the semiconductor devices on a test socket of a test site to carry out a demanded test thereon, and classifies the tested semiconductor devices into various levels to unload them on the tray. The handler carries out such steps repeatedly to perform the tests.
FIG. 1 illustrates a layout of a general handler for semiconductor device test.
Referring to FIG. 1, in a front part of a handler body 1, formed are a loading unit 2 on which trays receiving test-expecting semiconductor devices thereon are loaded and an unloading unit 3 having a plurality of trays receiving test-completed semiconductor devices classified into good products and fail products in accordance with test results. And, a soaking plate 7 is installed in rear of the loading unit 2. The soaking plate 7 includes a heating means (not shown in the drawing) and a cooling means (not shown in the drawing) inside to heat or cool the test-expecting semiconductor devices to a predetermined temperature for temperature test.
And, a reject multi-stacker 5, on which a plurality of trays are loaded to receive the semiconductor devices classified by grade into the fail product's according to the test results, is installed in rear of the unloading unit 3.
In a test site 10 located at the foremost rear part of the handler body 1, at least one test socket 11 connected electrically to an external testing device is installed to test a performance of each of the semiconductor devices. Over the test socket 11, formed are first and second index heads 12a and 12b installed to move horizontally to pick up to load the semiconductor devices, which are transferred to standby positions at both sides of the test socket 11, on the test sockets 11 as well as to pick up to retransfer the tested semiconductor devices on the test sockets 11 to the standby positions at both sides.
In the very front of the test site 10, first and second shuttles 8a and 8b are installed to move back and forth. The first and second shuttles 8a and 8b receive to transfer the semiconductor devices from the loading unit 2 or the soaking plate 7 to the standby positions at both sides of the test sockets 11 of the test site 10. At one sides of the first and second shuttles 8a and 8b, third and fourth shuttles 9a and 9b are installed to move back and forth, respectively. The third and fourth shuttles 9a and 9b receive to transfer the test-completed semiconductor devices from the test site 10 to an outside of the test site 10.
Fixing frames 13 are installed at the front end of the handler body 1 and over the very front side of the test site 10 across the handler body 1, respectively. A pair of movable frames 14a and 14b are installed at the fixing frames 13 to move right and left along the fixing frames 13. And, two device transfer unit 15 are installed at the movable frames 14a and 14b to move along the movable frames 14a and 14b to pick up semiconductor devices, respectively. Each of the device transfer unit 15 includes a plurality of pickers (not shown in the drawing) to transport a plurality of the semiconductor devices simultaneously.
Meanwhile, a handler is constituted to carry out a test on such semiconductor devices as QFP, BGA, SOP, and the like. After one species of the semiconductor devices have been tested, another species of the semiconductor devices are tested. In such a case, the tray and change kits including the soaking plate 7, shuttles 8a, 8b, 9a, and 9c, test sockets 11, and the like are replaced by another change kits fitting to the semiconductor device species to carry out the test.
In this case, the change kits replaced according to the species of the test-expecting semiconductor devices differ from each other in sizes and thickness and the semiconductor device species differ from each other in thickness. Hence, working sections of the device transfer unit 15 should be reset.
However, in measuring the working height according to the semiconductor species and the options of the change kits to be replaced, an operator moves the device transfer unit 15 to pick & place positions one by one and then moves the device transfer unit 15 upward and downward to set up the working height. In such a case, a probability of error occurrence during input is high and a working height setup takes too much time. Hence, daily productivity is reduced and overall efficiency of the test work is decreased.